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How do I log errors and warnings into a file?
How do I turn on all error and warnings and log them to a file, but to set up all of that within the script (not changing anything in php.ini)?
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What is a NullReferenceException, and how do I fix it?
.... This means you either set it to null, or you never set it to anything at all.
Like anything else, null gets passed around. If it is null in method "A", it could be that method "B" passed a null to method "A".
null can have different meanings:
Object variables which are uninitialized and hence poi...
transform object to array with lodash
...
You can do
var arr = _.values(obj);
For documentation see here.
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InputStream from a URL
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Calling this method in UI thread in Android will raise an exception. Do it in a background thread. Use Bolts-Android
– Behrouz.M
Mar 6 '19 at 10:16
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Writing a Python list of lists to a csv file
...It kinda makes sense in hindsight, but not informative of where to look at all.
– Rambatino
May 25 '18 at 7:30
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Declaring an enum within a class
...uct Color
{
enum Type
{
Red, Green, Black
};
Type t_;
Color(Type t) : t_(t) {}
operator Type () const {return t_;}
private:
//prevent automatic conversion for any other built-in types such as bool, int, etc
template<typename T>
operator T () const;
};
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Cartesian product of x and y array points into single array of 2D points
... 5],
[2, 5],
[3, 5]])
See Using numpy to build an array of all combinations of two arrays for a general solution for computing the Cartesian product of N arrays.
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How do I select a random value from an enumeration?
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Use Enum.GetValues to retrieve an array of all values. Then select a random array item.
static Random _R = new Random ();
static T RandomEnumValue<T> ()
{
var v = Enum.GetValues (typeof (T));
return (T) v.GetValue (_R.Next(v.Length));
}
Test:
for (in...
Pretty-print an entire Pandas Series / DataFrame
...: # more options can be specified also
print(df)
This will automatically return the options to their previous values.
If you are working on jupyter-notebook, using display(df) instead of print(df) will use jupyter rich display logic (like so).
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What is the difference (if any) between Html.Partial(view, model) and Html.RenderPartial(view,model)
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The usage of the two methods is slightly different:
@Html.Partial("_yourPartialView")
@{ Html.RenderPartial("_yourPartialView "); }
The choice of which to use depends on your requirements. If you need
to further manipulate the string being injected in the response
stream, you shoul...